1. Field of the Invention
This invention relates to the covalent attachment of a substance such as a biological moiety to a surface such as, for example, a glass surface, metal or metal oxide. One area of use of the present invention is in the field of solid phase chemical synthesis, particularly solid phase synthesis of oligomer arrays, or attachment of oligonucleotides and polynucleotides to surfaces, e.g., arrays of polynucleotides.
In the field of diagnostics and therapeutics, it is often useful to attach species to a surface. One important application is in solid phase chemical synthesis wherein initial derivatization of a substrate surface enables synthesis of polymers such as oligonucleotides and peptides on the substrate itself. Intact oligonucleotides, polynucleotides, peptides or proteins may be attached to a surface or a substrate in a similar manner. Support bound oligomer arrays, particularly oligonucleotide arrays, may be used in screening studies for determination of binding affinity. Modification of surfaces for use in chemical synthesis has been described. See, for example, U.S. Pat. No. 5,624,711 (Sundberg), U.S. Pat. No. 5,266,222 (Willis) and U.S. Pat. No. 40 5,137,765 (Farnsworth).
In modifying siliceous or metal oxide surfaces, one technique that has been used is derivatization with bifunctional silanes, i.e., silanes having a first functional group enabling covalent binding to the surface (often an Si-halogen or Si-alkoxy group, as in --SiCl.sub.3 or --Si(OCH.sub.3).sub.3, respectively) and a second functional group that can impart the desired chemical and/or physical modifications to the surface. A problem with this type of surface modification, however, is that incorporation of a desirable surface chemical functionality provided by the second functional group requires chemical compatibility between the two functional groups. The presence of the second functional group can affect the density, uniformity and reproducibility of the surface coverage.
There are a number of applications for polynucleotides bound to solid supports. For example, such supports may be used to test for the presence of mutations in complex DNA's, e.g., for disease loci in humans. They can be used also to select specific nucleic acids form complex mixtures, for example, specific mRNA's from a whole cell population.
In the field of bioscience, arrays of oligonucleotide probes, fabricated or deposited on a surface, are used to identify DNA sequences in cell matter. The arrays may be used for conducting cell study, for diagnosing disease, identifying gene expression, monitoring drug response, determination of viral load, identifying genetic polymorphisms, and the like. Significant morbidity and mortality are associated with infectious diseases and genetically inherited disorders. More rapid and accurate diagnostic methods are required for better monitoring and treatment of these conditions. Molecular methods using DNA probes, nucleic acid hybridization and in vitro amplification techniques are promising methods offering advantages to conventional methods used for patient diagnoses.
Proteins have been immobilized in the past on a wide variety of solid supports for various known applications including analysis, separation, synthesis and detection of biological and other materials. Often hydrophilic polymers have been used to immobilize the proteins because it is less difficult to attach proteins to polymers than to inorganic materials. However, there is an increasing need to immobilize functional organic material such as proteins on inorganic material such as silica, glass, silicon, metals and the like. In solid phase technology the reagent or reagents used in the procedure are usually immobilized by being coated or bonded either covalently or by adsorption to the solid phase material.
Biologically active polypeptides or proteins that are attached to insoluble carrier material, such as polymeric particles, have been used in a variety of ways. For example, the diagnosis of pathological or other conditions in human beings and animals is often carried out using immunological principles for the detection of an immunologically reactive species, for example, antibodies or an antigen, in the body fluids of the person or animal. Other proteins and amine-containing compounds, such as enzymes, avidin, biotin or polysaccharides, have been covalently linked to various carrier materials for use in affinity chromatography, enzymatic reactions, specific binding reactions and immunoassays.
A variety of methods have been reported for the covalent attachment of ligands to a surface. Typically, these reactions are performed by the reaction of an active functional group on the ligand with an activated functional group on the surface. Other reactions, such are UV cross-linking, can be used for covalent attachment but are not functional group type-specific. Functional group specific methods previously described include the activation of surfaces with cyanogen bromide, N-hydroxysuccinimide esters, carbonyl diimidazole, carbodiimides, azlactones, cyanuric chlorides, organic sulfonyl chlorides, divinyl sulphone, nitrophenyl esters, iodoacetyl, maleimide, epoxy, hydrazide, reductive amination, diazonium salts and Mannich condensations. Ligands that react with the activated surface include amines, alcohols, carboxylic acids, thiols, carbonyls, and compounds containing active hydrogens. Other approaches involve treating the surface of an inorganic support with N-(2-aminoethyl)-3-aminopropyltrimethoxysilane or 3-aminopropyltriethoxysilane with the amino group as an attachment point.
Many of the known procedures for attaching monomers, oligomers and polymers to surfaces to form arrays exhibit a significant amount of batch to batch variability. This is often not acceptable because there is a significant impact on the accuracy and reproducibility of quantitative determinations. For such determinations it is important to be able to prepare arrays that show consistency in the performance of the array particularly from one batch to the next.
The present invention is directed to the aforementioned need in the art and provides a way of obtaining a high density, reproducible and uniform coverage of a surface while avoiding the aforementioned problems and difficulties associated with the procedures in the art.
2. Description of the Related Art
U.S. Pat. No. 5,258,041 (Guire, et al.) discloses a method of biomolecule attachment to hydrophobic surfaces.
U.S. Pat. No. 5,043,278 (Nagaoka, et al.) discusses physiologically active substance fixed to a thin fiber carrier with an alkylene oxide chain.
U.S. Pat. No. 5,314,830 (Anderson, et al.) discloses immobilized hydrophobically modified antibodies.
U.S. Pat. No. 5,624,711 (Sundberg, et al.) discusses derivatization of solid supports and methods for oligomer synthesis.
U.S. Pat. No., 4,680,121 (Ramsden, et al.) discloses bonded phase of silica for solid phase extraction.
U.S. Pat. No. 5,002,884 (Kobayashi, et al.) discusses immobilization of physiologically active substances on an inorganic support.
U.S. Pat. No. 5,436,327 (Southern, et al.) discloses support bound oligonucleotides.
U.S. Pat. No. 5,585,236 (Bonn, et al.) discusses nucleic acid separation on alkylated nonporous polymer beads.
U.S. Pat. No. 5,601,979 (Wong 1) discloses preparation and use of magnetic controlled pore glass having oligonucleotides synthesized thereon.
U.S. Pat. No. 5,637,201 (Raguse, et al.) discusses sensor membranes.
U.S. Pat. No. 5,614,263 (Ogawa, et al.) discusses hydrophilic chemically adsorbed film and method of manufacturing the same.
U.S. Pat. No. 5,610,274 (Wong 2) discloses preparation and use of magnetic porous inorganic materials.
U.S. Pat. No. 4,490,216 (McConnell) discusses lipid membrane electroanalytical elements and method of analysis therewith.
U.S. Pat. No. 4,572,901 (Ceriani, et al.) discusses a method and composition for protein immobilization.
U.S. Pat. No. 4,637,861 (Knill, et al) discusses stabilized lipid membrane based device and method of analysis.
U.S. Pat. No. 9839481 (Anderson, et al.) discloses attachment of nucleic acids to solid phase surfaces via disulphide bonds.